The film indicates Carol's personal chaos with its fragmented, sometimes hard-to-follow storyline, which cuts back and forth in time. Bent over his microscope, Dr. Galeano isn't a likely action movie hero, and neither are his cohorts; the change in this old story's plot suits our current times. And Carol's perspective also limits potential philosophical questions. When her ex, Tucker (Jeremy Northam), tries to infect their young son, Oliver (Jackson Bond), with the organism, he insists that it's for the boy's good, to be part of "our world," where everyone feels peaceful and "the same" (news reports reveal that the rest of the world is changing: Darfur declares a ceasefire, the Iraqi president calls off suicide bombings, and Hillary Clinton and George W. Bush appear together, all smiles and agreements). As Tucker puts it, this conformity by force isn't so different from the pills Carol prescribes for her unhappy patients: Everyone just wants to "feel better."
The hitch is that the new world cannot brook difference, so anyone who's immune to the transition or otherwise resists it is eliminated -- brutally. And so the film undergoes its own change, from sharp paranoid thriller to noisy action flick, with lots of shooting and cars crashing, a chase in D.C.'s metro system, and a by-the-numbers helicopter rescue. Sadly, all this physical commotion eventually prevails over the film's more complicated questions about fear, independence, and social order.